Telecommunications networks are increasingly used to deliver data services to network users. These services may be offered by an operator of the network or may be offered, via the network, by independent service providers. When a user is within the geographic coverage area of their home network, that is the network to which they subscribe, data services are requested and delivered via a gateway support node within the home network, through which data traffic may be exchanged with an external network such as the internet. The majority of network operators offer varying levels of data access for users within their different subscription offerings.
When a network user is outside the geographic coverage area of their home network, they may still access voice and data services by connecting to their home network via a visited network with which their home network has a roaming agreement. When roaming, data traffic from the user is routed through the visited network to the home network, and incoming data traffic is routed via the home network to the visited network before reaching the user. While this arrangement offers the advantage of maintaining access to data services for a roaming user, roaming data access typically results in high charges for roaming data services, as the cost of data traffic through both the home and visited networks is covered by the user. Consequently, many users disable the data service capability within their wireless device in order to avoid these high charges.
The practice of disabling mobile data when roaming is disadvantageous both for the user and for network operators. Home and visited networks are deprived of revenue generating data traffic, and the user is obliged to go without data services which they are accustomed to accessing. Some data services may be of even greater practical value to a user when travelling outside their home network coverage area, for example when travelling internationally, and it is thus a significant disadvantage for users to be constrained to go without these services when roaming.
Additionally, the step of disabling data service capability on a wireless device may not in fact stop all data traffic from leaving the device. In the majority of cases, disabling data on a wireless device means that data traffic is stopped in a firewall or proxy within the device. However, a firewall or proxy may not stop all types of data traffic from being delivered from the device. For example, Domain Name Server (DNS) lookup and/or certificate validation may not be stopped by a device firewall or proxy and a Packet Data Protocol (PDP) context may still be set up when an application is launched, even if data traffic is being stopped by a device firewall or proxy. This breakthrough traffic may incur data charges for the user even though the user is not profiting from the data service.